PHYSICOCHEMICAL AND ELECTROCATALYTIC STUDIES OF SnO2-GUAR GUM NANOCOMPOSITE

Abstract

In this project report, I tried to present results of the studies related to fabrication of a metal oxide based efficient non-enzymatic sensor using an interface based on sol-gel derived nanostructured tin oxide (SnO2). A colloidal solution of prepared nanostructures has been electrophoretically deposited (EPD) onto an indium-tin-oxide (ITO) glass substrate. The structural and morphological studies of SnO2 nanoparticles have been carried out by X-ray diffraction (XRD) (particle size 10.6 nm) , scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), UV-visible spectroscopy (UVVis), photoluminescence spectroscopy (PL) and Fourier transform infrared (FTIR) spectroscopic techniques. Guar gum (a biopolymer) was used as a matrix to prepare the nanocomposite. The SnO2 nanoparticles were then ultrasonically dispersed in guar gum (GG) solution, and then used to form SnO2-GG nanocomposite film by drop casting method on the ITO plate. The SnO2- GG/ITO nanocomposite film was found to provide improved sensing characteristics to the electrode interface in terms of electroactive surface area, diffusion coefficient, charge transfer rate constant and electron transfer kinetics. This interfacial platform has been used for fabrication of a non-enzymatic sensor for hydrazine sensing. The results of response studies of the fabricated SnO2-GG/ITO electrode show a linear range of 2-22 mM, detection limit of 2.769 mM, and high sensitivity of 5.72 μMcm-2 with a response time of 35 s. The utilization of this SnO2 modified electrode for electo-oxidation of hydrazine offers an efficient strategy and a novel interface for application of tin oxide in the field of electrochemical sensors.